1. Field of the Invention
The present invention relates in general to a method for managing digital data files, such as a digital audio data file and a digital video data file, and a recording medium including a program for performing such management. The present invention also relates to a method and device for preventing an illegal distribution of digital data contents and one or more computer programs for implementing the same.
2. Description of the Background Art
Generally, an MP3 player is a type of digital data player for processing digital data files. The MP3 player is new notional, portable digital audio equipment capable of readily downloading and reproducing desired music from a computer communication network using an audio data compression coding technique prescribed in MPEG1 Layer3. In particular, the MP3 player has few faults and excellent sound quality because it stores music in the form of an MP3 file. Further, the MP3 player is small in size and light in weight, thereby allowing high activity uses such as being carried during physical exercise. For these reasons, this product is being touted as an alternative to a portable cassette tape recorder and compact disk (CD) player.
For use in such an MP3 player, a digital data file is downloaded from a file supplier (server) to a personal computer terminal via a communication network such as the Internet and, in turn, to the MP3 player. The digital data file downloaded as mentioned above may be uploaded from the MP3 player to the personal computer terminal, thereby causing a problem in regard to copyright infringement.
On the other hand, when the supply of digital data players, like the MP3 player, become more widely spread and issues such a copyright protection are settled between digital data file suppliers and copyright holders, digital data file purchasing routes will be extended to vending machines, encoders, etc. In this case, file uploading from a digital data player to, for example, a personal computer terminal will have to be permitted at least under certain restrictions.
However, there is no conventional technique capable of, when a digital data file is intended to be uploaded from the digital data player to the personal computer terminal, identifying a provider of the digital data file and permitting the uploading within limits in accordance with the identified result. This fact becomes an obstacle to the proliferation of the digital data player.